EX-9121 lipe: Trivial improvements for report merging

EX-9121 lipe: Trivial improvements for report merging

Small changes that do not affect the functionality, but allow to
reuse some functions in other parts of lipe3, for example in the
utility for merging different stats reports.

Test-Parameters: trivial testlist=sanity-lipe-scan3,sanity-lipe-find3
Signed-off-by: Vitaliy Kuznetsov <vkuznetsov@ddn.com>
Change-Id: I1bc2d4b22e57a369acea86bf60d8f460c5b3b093
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/55045
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>